There are many products, as exemplified by paper tissue, toweling and napkins, etc., which are commonly provided to consumers in stacked form as packs of folded or interfolded individual sheets. These packs of stacked sheets are often staple items which must be produced at very low cost. Producing such products at low cost typically requires the use of high-speed processes and equipment. Such processes are not limited to the production and delivery of paper products, but are widely used in the production of other products such as foil, textile, synthetic sheeting and other industries.
Experience has shown that the steps of cutting individual sheets from a web or webs of material, and folding or interfolding the individual sheets to form a stack of folded sheets can be accomplished at higher speeds than subsequent downstream processes such as: separating a stack of the folded material into individual packs having a desired number of sheets; performing secondary folding of a lead or trailing sheet of each pack; and delivering the completed pack to downstream packaging equipment used to wrap or otherwise prepare the completed packs for delivery and sale.
In the past, a variety of approaches have been utilized for: separating stacks of folded sheets into packs; performing any necessary secondary folding operations; and transporting the completed packs to downstream processing equipment. Some of these prior approaches are illustrated in the following US patents which are commonly assigned to the assignee of the present invention: U.S. Pat. Nos. 4,770,402 to Couturier; 4,874,158 to Retzloff; 6,641,358 to Schmidt et al.; and 6,322,315 to Schmidt et al.
Although all of the prior approaches described in the above-listed patents of the assignee of the present invention have been, and continue to be, highly successful in their application, further improvement is desirable. Specifically, a continuing need exists for improved apparatuses and methods for separating a completed pack of folded or interfolded sheets from a partly complete pack, while continuing to build the partly completed pack, and transporting the completed pack to downstream operations at higher speed than has previously been attainable. It is also desirable that such improved apparatuses and methods be configured to allow clearing of jams and misfeeds more quickly and with less downtime than prior approaches. It is further desirable that an improved apparatus and/or method be capable of performing final folding operations in a more flexible manner to permit faster system operation.